1. Field of the Invention
The instant invention relates to that field of devices consisting of articles of manufacture known as safety caps. Specifically, the instant invention is a compressed gas bottle high pressure release cap.
2. Background Information
The prior art known to applicant discloses that single use safety caps are reasonably well known. The single use safety cap is most often intended to prevent unwanted intrusion of foreign matter into the area protected by the cap, or to provide quick visual indication as to whether or not the area protected by the cap has been tampered with. These safety caps have been utilized in conjunction with a great number of different containers, the containers holding diverse materials. Applicant is aware of tamperproof and tamper evident safety caps intended to be used with various liquids stored in pressurized containers. For example, in Tamperproof Container Closure issued to J. W. Soffer, U.S. Pat. No. 2,643,015, Jun. 23, 1953, the tamper proof cap is a frusto-conical cap having a closed end and an open end, the open end having teeth for gripping the container to be protected, and a pull tab which permits the user to break the safety cap and remove it prior to use of the container.
Another example of tamper proof caps may be found in Tamper Indicating Cap Seal for Container Valves, issued to Charles Fuehrer, U.S. Pat. No. 4,712,705, Dec. 15, 1987, the tamper indicating cap is nearly identical to Soffer, but has been adapted for use on beverage tanks having valves or quick disconnect coupling plugs by essentially including another depending skirt to the device disclosed in Stoffer, and a series of bumps or protrusions on the interior wall which mate up with the various indentations found on the valves of common beverage tanks.
Unfortunately, none of the above prior art patents provides a safe, efficient and easy to use way to prevent intrusion into a gas cylinder valve, while at the same time providing a safe means for escape of pressurized gas.
In both Soffer '015 and Fuehrer '705, the cap is intended to remain in place once attached, and no provision is made to allow the safe escape of high pressure gas from the container. In fact, the stated objective in both of these patents is to provide a cap which cannot be removed without causing visible damage to the cap. This is a critical flaw.
Those who routinely handle pressurized gas canisters (for example, those who supply hospitals and others with so-called "oxygen bottles") know that on occasion high pressure gas may escape from the cylinder valve. Escapes such as this are rarely intended or anticipated. When such an escape of high pressure gas occurs, anything between the valve and the outside environment will be subjected to a sudden stream of high velocity gas. All too often it is the safety cap which takes the brunt of the force of the escaping gas. The result is a safety cap acting as a high velocity, and potentially highly dangerous, projectile as it is blown away from the valve.
In the event that high pressure gas escapes while the Fuehrer '705 cap is in place, the sudden high pressure release against the underside surface of the top of the cap is extremely likely to dislodge the cap and send it flying away from the container at a dangerous velocity. Soffer '015, being of the same essential construction, is just as likely to be dislodged and become a potentially dangerous missile.